Experimental validation of simulated metering and power loss characteristics of the rotary tubular spool valve.

This paper presents the results of numerical and experimental performance evaluation of the rotary tubular spool valve. The aim of this work is to develop further the novel design of the tubular spool valve by confirming validity of the simulation model and its results, thereby proving the valve’s potential to represent a feasible and more efficient alternative to conventionally used spool valves avoiding the use of more expensive two stage valve configurations. In this research the valve performance is assessed through numerical modelling and experimental studies of metering and pressure loss characteristics of the valve. This paper demonstrates that the used valve model yields the results, which agree well with the conducted experimental study. Therefore, validation of the numerical model and the modelling results in the form of theoretical valve characteristics was accomplished. Firstly, the paper presents details of a numerical approach employed to evaluate valve performance and then analyzes the simulation results. Next, the valve performance is experimentally validated by testing a prototype valve on a hydraulic test rig capable of measuring the volume flow rate, pressure levels in up- and downstream lines of the valve over the entire spool angular stroke. Initially, average discrepancies between modelling and test results were 52.46% for the metering and 82.78% for the pressure drop function. Correcting the model geometry aimed at eliminating differences between the valve model and the practically used prototype-test rig system enabled reduction of the error between experiment and modelling by 47.75% for the pressure loss function. This confirmed validity of the simulated characteristics of the valve. The benchmark comparison of pressure losses confirmed average 71.66% energy dissipation reduction compared to the industry-available analogue valve.